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choconostle123

Member

Registered: 2020-09-16

Posts: 11

doubt about programing algorithm called "on grid method"

hello everyone, i am learning to programing the algorithm called "on-grid method" to generate the basin, but i have a problem

i use the wave function of hydrogen molecule

my algorithm  correctly assigns most of the points to the basin of the hydrogen 1 and hydrogen 2 (the bcp is at (0,0,0), and my nuclear attractors in (0,0,+-0.584)) but in the plane xy where is the bond critical point (points like (0,2,0) (2,2,0) (1.8,2,0)) these kind of points are assigned to the basis of hydrogen 1 so when i want to integrating the density, the density in the basin of hydrogen 1 has major density than basis of hydrogen 2 because if use 41 points of size  in the end of my  algorithm hydrogen1 has 36141 points in the basin and hydrogen2  34460

so i don't know wath to do for improving my algorithm 

Last edited by choconostle123 (2023-04-26 17:54:37)

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,830

Website

Re: doubt about programing algorithm called "on grid method"

Do you mean basin? Basin and basis have quite different meanings.

The only way of improving accuracy (or decreasing the difference of result for equivalent atoms) under the framework of on-grid algorithm is using a smaller grid spacing. The result difference of the two atoms cannot be fully eliminated (unless you employ a special grid distribution, which is fully in line with molecular symmetry)

choconostle123

Member

Registered: 2020-09-16

Posts: 11

Re: doubt about programing algorithm called "on grid method"

sorry is basin, I corrected it, oooo now I understand, thanks for your support i will train use a smaller grid spacing